Heterocyclic phosphorus compounds and process for their manufacture

ABSTRACT

Heterocyclic phosphorus compounds with a hetero-ring containing eight ring members, namely two carbon, two nitrogen and two oxygen atoms are provided. These compounds are manufactured by reacting 2 mols of at least one phosphonocarboxylic acid amide with at least 4 mols of anhydrous formaldehyde in the presence of an acid catalyst and in the absence of water. The phosphorous compounds are used for flameproofing and creaseproofing cellulose-containing textile material. They may be optionally used together with an aminoplast precondensate.

United States Patent Hermann Nachbur Dornach; Joerg Kern, Oberwil Basel-land; Arthur [72] Inventors Maeder, Theryvil, all of Switz erla r 1d [50] Field of Search 260/338 [5 6] I References Cited I UNITED STATES PATENTS 3,38l,062 4/1968 Zahir 260/927 Primary Examiner-Norma S. Milestone Attorneys-Harry Goldsmith, Joseph G. Kolodny and Mario A. Monaco ABSTRACT: Heterocyclic phosphorus compounds with a hetero-ring containing eight ring members, namely two carbon, two nitrogen and two oxygen atoms are provided. These compounds are manufactured by reacting 2 mols of at least one phosphonocarboxylic acid amide with at least 4 mols of anhydrous formaldehyde in the presence of an acid catalyst and in the absence of water. The phosphorous compounds are used for flameproofing and creaseproofing cellulose-containing textile material. They may be optionally used together with an aminoplast precondensate.

dehyde is here used in the form of paraformaldehyde.

To manufacture the phosphorus compounds of formulas l to (4), phosphonocarboxylic acid amides of formula wherein R,, R R, and R, each denote an alkyl, halogenalkyl or alkenyl residue with at most four carbon atoms each andX 15 h in R d X have th indi t d ignifi an e e and X each represent a methyl residue or preferably a hydrogen atom.

Preferred compounds are symmetrical phosphorus compounds of formula preferably used.

Compounds of particular interest are phosphonocarboxylic acid amides of formula wherein R and X have the indicated significance.

Compounds of particular interest are phosphorus compounds'of formula wherein R represents a methyl or ethyl residue. Acompound which has above all proved valuable is the phosphorus compound of formula The reaction is advantageously carried out at elevated temperature, preferably 80 to 150C. The usualagents which split off water, such as for example sulfuric acid, phosphoric The phosphorus compounds of formula l are appropriately manufactured by reacting (a) 2 mols of atleast one phosphonocarboxylic acid amide of formula CH2]CHCO-NH2 X Y RFO acid or especially p-toluenesulfonic acid are used as .acid catalysts required for this reaction. ln certain cases it proves advantageous to carry out the reaction in the presence of a solvent'which is inert towards the reagents,-such as forexample benzene, toluene, xylene or methanol. On the other hand the reaction can also be carried out in the melt, .thatis' to say without solvents.

The p'hosphonocarboxylic acid amides of formula (5) used for the manufacture of the phosphorus compounds of formula (1) to (4) are in themselves known and can be manufactured according to kncwnmethods.

The reaction of the phosphonocarboxylic acidamides of formula (5) with formaldehyde probably takes, place via two, and possibly three, stages by these phosphonocarboxylic acid amides first-being dimethylolated at the amide nitrogen atom and two molecules of these dimethylol compounds thereafter forming an eight-membered heteroring, with waterbeing split off:

In order to manufacture the phosphorus compounds of forguanamines, for example benzoguanamine. acetoguanamine mulas (l) to (4), it is also possible to proceed by starting from or also diguanamines may be mentioned. Further possible sub- 2 mols of the dimethylolated compounds of formula (5), disstances are: alkylureas or arylureas and alkylthioureas or solving these in an inert organic solventand effecting the ring arylthioureas, alkyleneureas'or alkylenediureas, for example closure between two molecules of the dimethylol compounds ethyleneurea, propyleneurea, acetylenediurea, or especially at a time at elevated temperature in the presence of an acid 4,5-dihydroxyimidazolidone-Z and derivatives thereof, for excatalyst and with water being split off.

The invention also relates to a process for the flameproofmg and greaseproofing of cellulose-containing fiber materials characterized in that an aqueous preparation which contains at least one phosphorus compound of one of the formulas (l) to (4) and optionally a curable aminoplastic precondensate to these materials, thereafter drying the materials and subjecting them to a treatment at elevated temperature.

In particular. the phosphorus compounds of formula (I) are used for flameproofing and creaseproofing cellulose-containing textile material. Phosphorus compounds of formulas (2) and (3) are preferred, and the process for flameproofing and creaseprooftng is of very particular interest if the compound of formula (4) is used.

The pH value of the aqueous preparations containing the compounds of formula (1) is advantageously less than 5, in particular less than 3. in order to achieve this, mineral acids such as sulfuric acid, nitric acid, orthophosphoric acid or hydrochloric acid are added to the preparations. Instead of the acids themselves, especially hydrochloric acid, it is also possible to use compounds from which the corresponding acids are easily, for example even without warming, formed in water by hydrolysis. As examples, there may here be mentioned phosphorus trichloride, phosphorus pentachloride, phosphorus oxychloride, thionyl chloride, sulfuryl chloride, cyanuryl chloride, acetyl chloride and chloracetyl chloride. These compounds exclusively yield acid decomposition products, for example cyanuric acid and hydrochloric acid, on hydrolysis. Now it can be advantageous to use the acid mixtures corresponding to the hydrolysis products of one of the compounds just mentioned in place of one of the strong acids mentioned, that is to say for. example to use, instead of hydrochloric acid or orthophosphoric acid alone, a mixture of hydrochloric acid and orthophosphoric acid which corresponds to phosphorus pentachloride, appropriately in a molecular ratio of 5: l.

The preparations for flameproofing and creaseproofing can also contain a latent acid catalyst for accelerating the cure of the aminoplast precondensate which is optionally present and for cross-linking the compounds of formula l As latent acid catalysts it is possible to use the catalysts which are known for curing aminoplasts on cellulose-containing material, for example ammonium chloride, ammonium dihydrogen orthophosphate, magnesium chloride, zinc nitrate and others.

Apart from the compounds of formula l) and the additives which are required for adjusting the pH value, the preparations to be used according to the invention can contain yet further substances. An addition of aminoplast precondensates is advantageous for achieving a good wash-resistant flameproof finish, but is not necessary.

By aminoplast precondensates there are understood addition products of formaldehyde to nitrogen compounds which can be methylolated. 1,3,5-Amino-triazines such as N-substituted melarnines, for example N-butylmelamine, N- trihalogenomethylmelamines, as well as ammeline,

ample the 4,5-dihydroxyimidazolidone-2 which is substituted in the 4-position at the hydroxyl group by the residue CH,CH,CO-NHCH,OH. The methylol compounds of a urea, an ethyleneurea or of melamine are preferred. Particularly valuable products are in general provided by products which are as highly methylolated as possible. Suitable aminoplast precondensates areboth predominantly monomolecular and also more highly precondensed aminoplasts.

It is also possible to use the ethers of these aminoplast precondensates together withthe compounds of formula (l Advantageous compounds are for example the ethers of alkanols such as methanol, ethanol, n-propanol, isopropanol, nbutanol or pentanols. It is however appropriate for these aminoplast precondensates to be water soluble, as for example pentamethylolmelamine-dimethyl-ether.

It can also be advantageous for the preparations to contain a copolymer, obtainable by polymerization in aqueous emulsion, of (a) 0.25 to 10 percent of an alkaline earth salt of an afi-ethylenically unsaturated monocarboxylic acid, (b) 0.25 to 30 percent of a N-methylolamide .or N-methylolamideether of an a,B-ethylenically unsaturated monocarboxylic or dicarboxylic acid and (c) 99.5 to60 percent of at least one other copolymerizable compound. These copolymers and their manufacture are also known. The tear resistance and scouring resistance of the treated fiber material can be advantageously influenced by the conjoint use of such a copolymer. I

As further additive which is'of advantage in some cases, a plasticizing dressing should be mentioned, for example an aqueous polyethylene emulsion or ethylene copolymer emulsion.

It can also prove appropriate to add an emulsifier. for example a nonionic emulsifier, to the preparations.

The content of compound of formula (1) in the aqueous preparation is appropriately such that 10 to 28 percent is applied to the material to be treated. Here it is necessary to take into account that the commercially available textile materials of native or regenerated cellulose can take up between 50 and 120 percent of an aqueous preparation. As a rule the aqueous preparations contain to 500 g./l. preferably 250 to 400 g./l., of phosphorus compound of formula l The amount of the additive required to adjust the hydrogen ion concentration to a value of less than 5 depends on the selected value itself and on the nature of the additive, though in any case it is not possible to go below a certain minimum. A certain excess above this minimum amount is generally to be recommended. Large excesses offer no advantages and can even prove harmful.

if a polymer of the indicated nature is further added to the preparation, then this is preferably done in small amounts, for example l to 10 percent relative to the amount of the compound of formula (l). The same is true of a possible plasticizer, where the appropriate amounts can again be l to percent.

The preparations are now applied to the cellulose-containing fiber materials, for example linen, cotton, acetate rayon, viscose rayon or fiber mixtures of such materials and others such as wool, polyamide or polyester fibers, and this can be carried out in a manner which is in itself known. Preferably, piece goods are used and these are impregnated on a padder of the usual construction which is fed with the preparation at room temperature.

The fiber material impregnated in this way must now be dried, and this is appropriately done at temperatures of up to 100 C. Thereafter it is subjected to a dry heat treatment at temperatures above 100 C., for example between 130 and 200 C., and preferably between 150 and 180 C., the duration of which can be the shorter, the higher the temperature. This duration of warming is for example 2 to 6 minutes at temperatures of l50to 180 C I WWMM W H Rinsing with an acid-binding agent, preferably with aqueous sodium carbonate solution, for example at 40 C. to boiling temperature, and for 3 to 10 minutes, is advisable in the case of a strongly acid reaction medium.

As already indicated, it is possible to obtain flameproofing and creaseproofing finishes by the present process which largely remain preserved even after repeated washing or drycleaning and which do not cause any intolerable reduction in the mechanical textile properties of the treated material.

A particular advantage of the present process is the fact that the treated cellulose-containing fiber materials are simultaneously flameproof and creaseproof, even without the conjoint use of aminoplast precondensates. In particular, alongside the flameproof finish, the wet creaseproof properties of the treated fiber materials are significantly improved. A distinct improvement in the dry creasing angle can also be observed.

It is furthermore also possible to incorporate the phosphorus compounds of formula (1) into the spinning composition, for example of cellulose-Zlzacetate, provided they exhibit adequate solubility in organic solvents such as acetone. The incorporation is simple, the spinning poses no difficulties, and fabrics manufactured therefrom are thus flameproofed in a simple manner.

The percentages and parts in the examples which follow are units by weight, unless otherwise stated. The relationship of parts by volume to parts by weight is as of milliliter to gram.

7 EXAMPLE 1 One hundred and eighty-one parts (1 mol) of 3- (dimethylphosphono)apropionic acid amide, 120 parts (4 mols) of paraformaldehyde, 700 ml. of methanol as the solvent and 0.9 parts of p-toluenesulfonic acid as the catalyst are introduced into a stirred flask equipped with a reflux condenser and internal thermometer. This mixture is heated to the boil and left to react until no further 3- (dimethylphosphono)-propionic acid amide can be detected by means of a thin layer chromatogram. The reaction mixture is filtered while still hot and the filtrate is concentrated in vacuo on a waterbath. A slightly yellowish viscous oil remains as the reaction product and can be used without further purification. Yield: 205 parts 91.9 percent of theory.

The reaction product corresponds to formula (4). For further purification, the reaction product is diluted with the same volume of water. Thereafter it is extracted with n-hexane for 72 hours, in the course of which mainly thecompound of formula (5) is extracted. For yet further purification, the reaction product is distilled, with the main fraction being collected between 252 and 260 C. The structure of formula (4) can be confirmed by means of mass spectroscopy and infrared spectroscopy.

The compounds of examples 2 to 7 can also be purified and identified in an analogous manner.

EXAMPLE 2 One hundred and eighty-one parts (1 mol) of 3- (dimethylphosphono)-propionic acid amide, 123 parts (4 mols Cl-l O) of 97.5 percent strength paraformaldehyde and 0.9 part of p-toluenesulfonic acid monohydrate are warmed to 100 C. internal temperature, while stirring, in a 500 parts by volume stirred flask which is equipped with a condenser and thermometer, and are kept at this temperature for 6 hours. After this time, a sample of the reaction product shows, in a thin layer chromatogram, that practically all the 3- (dimethylphosphono)-propionic acid amide has reacted. The mixture is cooled to 60 C., 300 parts of methanol are added, and the whole cooled to 15 C. with rapid stirring. Thereafter the free paraformaldehyde is filtered off and the methanol is removed in vacuo.

Two hundred and forty-six parts of a yellowish clear product of low viscosity, corresponding to formula (4). are obtained.

EXAMPLE-3 1,357.5 parts (7.5 mols) of 3-(dimethylphosphono)- propionic acid amide, 922.5 parts (30 mols) of 97.5 percent strength Paraformaldehyde and 6.75 parts of p-toluenesulfonic acid, monohydrate in 1,500 parts of toluene are stirred for 3 hours at reflux temperature (100 C.) in a 5,000 parts by volume stirred flask equipped with a condenser and thermometer. Thereafter the mixture is cooled to 60 C., the toluene is decanted, 1,500 parts 'of methanol are added, the whole is cooled to 15 C. with rapid stirring, and free paraformaldehyde is filtered off. The methanol is then removed in vacuo.

One thousand eight hundred and thirty parts of a yellowish clear product of low viscosity corresponding to formula (4) are obtained.

EXAMPLE 4 One hundred and eighty-one parts (1 mol) of 3- (dimethylphosphon0)-propionic acid amide are mixed with 96 parts (3 mols) of 97.5 percent strength paraformaldehyde and 0.6 parts of magnesium oxide in a stirred flask of 500 volumes capacity, equipped with a thermometer and reflux condenser, and kept at 100 C. internal temperature for 30 minutes while stirring. After this time the content of bonded formaldehyde is 48.4 parts, corresponding to an percent formation of the dimethylol compound. The total CH O found is parts and the free C14 0 found is 41.6 parts.

" Thereafter 6 parts of p-toluenesulfonic acid monohydrate are added and the mixture is treated at C. for a further 10 hours and then cooled. The total CH,O found is still 5 1.5 parts and the free CH,O found is still 30 parts. Thus 38.5 parts of CH O can no longer be detected (as a result of ring closure), corresponding to a 64 percent formation of the product of formula (4 The product is thereafter stirred with 250 parts of methanol and excess paraformaldehyde is filtered off. The methanol is finally removed in vacuo at 45 C. The reaction product of formula (4) is a yellow clear syrup which can be regarded as 100 percent strength active substance.

EXAMPLE 5 One hundred and thirty-nine parts (0.5 mol) of (bis-2- chlorethyl)-phosphonopropionic acid amide are mixed with 61.5 parts of 97.5 percent strength paraformaldehyde (2 mols), 0.5 parts of p-toluenesulfonic acid monohydrate and 200 parts of toluene in a stirred flask of 200 volumes capacity equipped with a thermometer and reflux condenser, and are treated for 5 hours at 100 C. internal temperature. Thereafter the mixture is cooled, the toluene is separated off and the reaction product is stirred with 250 parts of methanol. Excess paraformaldehyde is filtered off and the methanol is removed in vacuo at 45 C. The residue is washed in 200 parts of water in a homogenizing apparatus and is adjusted to pH 6 with 30 parts of 2N sodium hydroxide solution. Thereafter the aqueous phase is separated off and the residue is again taken up in methanol and clarified by filtration, after which the methanol is again removed in vacuo. A yellowish syrup containing 100 percent of active substance is obtained. This reaction product corresponds to the formula ClCHz-CH7O O The reaction products of form u i are obtained in an analogous manner.

EXAMPLE 6 116.6 parts (0.5 mol) of diallylphosphonopropionic acid amide, 61.5 parts (2 mols) of 97.5 percent strength paraformaldehyde, 0.2 part of hydroquinone, 0.5 part of ptoluenesulfonic acid monohydrate and 200. parts of toluene are mixed in a stirred flask of 500 volumes capacity equipped with a thermometer and reflux condenser, and the mixture treated at 100 C. internal temperature for 10 hours. Thereafter it is cooled, the toluene is separated off, and the reaction product is stirred with 250 parts of methanol. Excess formaldehyde is filtered off and the methanol removed in vacuo at 45 C. One hundred and forty parts of a yellowish clear syrup which can be regarded as 100 percent strength active substance are obtained. The product still contains 12 parts of total CH,O. Furthermore, parts of paraformal dehydc wererecoveredbyfiltration,so th at 28 parts of CH O-- KJI cub cle-onto cinema 0N EXAMPLE 7 One hundred and thirty-three parts (0.5 mol) of 3-dibutylphosphonopropionic acid amide, 90.5 parts of 3- dimethylphosphonopropionic acid amide (0.5 mol), I23 parts (4 mols) of 97.5 percent strength paraformaldehyde and 1 part of p-toluenesulfonic acid monohydrate are mixed in a stirred flask of 500 volumes capacity equipped with a thermometer and reflux condenser, and treated for 10 hours at l00C. internal temperature. Thereafter the mixture is cooled and the reaction product stirred with 250 parts of methanol, after which the excess paraiormaldehyde is filtered off. Finally, the methanol is removed in vacuo at C. Two hundred and seventy-five parts of a syrupy product which still contains 24 parts of total CH,O and 5.6 parts of free CH,O are obtained. The product is a mixture which predominantly corresponds to formula l 3) but alongside this still contains 'compounds with free EXAMPLE 8 A cotton fabric is padded with one of the aqueous liquors A to D of table 1 below. The liquor uptake is 80 percent. The fabric is dried at to C. and thereafter cured for 4% minutes at 160 C. The fabricv is riow post-washed at the boil for 5 minutes in a solution which per liter of water contains 2 g. of anhydrous sodium carbonate, rinsed and dried. A part of the fabric is boiled five times or 10 times for 30 minutes in a solution which contains 2 g. of sodium carbonate and 5 g. of soap per liter of water (=SNV-4 wash).

The individual pieces of fabric are then tested for their flameproof property, tear strength and crease resistance. The results of these tests are also summarized in table I:

TABLE I Treated with preparation Untreated A B C D Flameproof property: 1

After 5 SNV-4 washes:

Burning time (see) Glowing time (sec.)

Burning time (sec.) Glowing time (see)...

Length of tear (cm.)

HBO

Crease resistance:

Monsanto picture 1 after single SNV-4 wash creasing angle 3 dry 1: 86 10w 110 109 104 Tear resistance: 4

Warp, percent... Weft, percent...

Vertical test according to DIN 63,906

creasing, rating 1: poor freedom from creasing.

Average of 10 measurements.

' Break ng load according to SNV-OSABL Thus a durable flameproofing and a good crease-free effect is simultaneously achieved with preparations A to D, and in particular without the addition of an aminoplastic percondensate. The mechanical textile properties of the fabrics are only insignificantly affected by the present finishes. The handle of the fabric finished in this way is also practically unchanged compared to the handle of the untreated fabric.

EXAMPLE 9 A cotton fabric is padded with one of the aqueous liquors E to l of table ll below. The liquor uptake is 80 percent. The fabric is dried at 80 C. and curing is then carried out for 4 minutes at 160 C. The fabric is now post-washed for minutes at the boil in a solution which per liter of water contains 2 g. of anhydrous sodium carbonate, rinsed and dried.

The concentrations of preparations E to l are so chosen that 44.5 g./l. of phosphorus is in each case contained in the bath.

The individual pieces of fabric are then tested for their flameproof property in accordance with the vertical test DIN 53,906. The results of this test are also summarized in table ll.

TABLE II 3. A phosphorus compound according to claim 2 of the formula 'R -O O P CHz- O- llaU mula mo-0 0 l am o-4110 Percent phosphorus Untreated E F Treated with preparation- Constituents:

Product according to Example-1, g. Product according to Example 2, g./l Product according to Example 7, g./1 Condensation product of 1 mol and 9 mols of ethylene 10 8 stren 05 or c a'id, gL a0 a0 a0 a0 30 pH value of the preparation. 2. 2 2.0 1. 0 2. 1 2. 1 Flarneproof property:

Burning time, sec Burns 0 0 0 0 0 Length of tear, cm"... 12.3 9.6 11.3 10.8 11.6

EXAMPLE 10 in which R and R, each is alkyl, chloroalkyl or allyl with at most four carbon atoms each and X is methyl or hydrogen.

2.- A ph ph ssqmpp d fth f ra e.-. a. n

in which R, is alkyl, chloroalkyl or allyl with at most four carbon atoms each and X is methyl or hydrogen.

5. A phosphorus compound according to claim 2 of the formula 6. A phosphorus compound according to claim 2 of the formula 7. A phosphorus compound according to claim 1 of the formula l v 12 011 0 RL-O 0 /P\ CHzOHzC l v CH'3O CHzCH C O-N /N-OC Ri-0 ClIa----(|J1i---C0- Nll2 We CH2OH2C 5 0 OCtHo -CH2H1C 0C4Hn in which R and X have the significance indicated in claim 2, 8. A process for the manufacture of a phosphorus comwith pound of the formula indicated in claim 1, which comprises b. at least 4 mols of anhydrous formaldehyde in the reacting presence of an acid catalyst used to split off water, in the a. 2 mols of at least one phosphonocarboxylic acid amide of absence of water, at 80 to 150 C. the formula I a: it t a a 

2. A phosphorus compound of the formula in which R1 is alkyl, chloroalkyl or allyl with at most four carbon atoms each and X is methyl or hydrogen.
 3. A phosphorus compound according to claim 2 of the formula in which R3 is methyl or ethyl.
 4. A phosphorus compound according to claim 2 of the formula
 5. A phosphorus compound according to claim 2 of the formula
 6. A phosphorus compound according to claim 2 of the formula
 7. A phosphorus compound according to claim 1 of the formula
 8. A process for the manufacture of a phosphorus compound of the formula indicated in claim 1, which comprises reacting a. 2 mols of at least one phosphonocarboxylic acid amide of the formula in which R1, and X have the significance indicated in claim 2, with b. at least 4 mols of anhydrous formaldehyde in the presence of an acid catalyst used to split off water, in the absence of water, at 80* to 150* C. 